CNI CNI-803D User Manual - User Manual

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User Guide to

CNI-803D

(Radio Packet Modem)

CNI Inc.

Overview _____________________________________________________ 3

Specification and features________________________________________ 3

A.Environment ________________________________________________ 3

B.General RF specifications _____________________________________ 3

C.Radio interface ______________________________________________ 3

D.Transmitter _________________________________________________ 4

E.Receiver____________________________________________________ 4

3. Circuit guide____________________________________________________ 5

A. RF circuit _________________________________________________ 5

B. LOGIC Circuit_________________________ ________________ ____7

4. Installation Guide_____________________________

______________ 9

1. Overview

CNI-803D, RPM(Radio Packet Modem), is a digital data communication equipment in

accordance with RD-LAP19.2 and MDC4800 specification. CNI-803D uses the frequency
ranges from 806MHz to 821Mhz for transmission, and from 851MHz to 866MHz for
reception.

This modem enables you to make data communication in two-way, and it also helps you

to enjoy various types of data services with full mobility due to support for roaming.

With ‘Interface Connector’ you can apply this modem to many kinds of machines to use

‘RD-LAP and MDC Asynchronous Serial Communication (NCL)’ protocol for
communication, and NCL commands enable you to monitor the operation during
communication.

Basic specification

Dimension

: 70

9mm

Weight

: 37 g

Supply voltage

: 5V

RF protocol

: RD_LAP19.2 on Data TAC4000

5000

Μ∆Χ4800 ον ∆ατα ΤΑΧ4000

Host protocol

: NCL1.2

2. Specification and features

Environment

Operation temperature : -30 ~ +60

Storage temperature

: -35 ~ +80

Humidity

: normal operation after 8 hours storage in 95% non-

condensed

General RF specifications

Modulation

: 4FSK for RD-LAP

2ΦΣΚ φορ Μ∆Χ

Mode

: half-duplex

Bit rate

: 19200bps for RD_LAP, 4800bps for MDC

Radio interface

Channel spacing

: 25KHz

Bandwidth

: 20KHz

Transmitter

Frequency

: 806 ~ 821 MHz

Transmit power

: 2Watt

Frequency stability

: 2.5ppm

Modulation stability

10%

FM deviation : 5.6KHz for RD_LAP (Logic +3+3-3-3)

2.5KHz for MDC (Logic +1-1)

Harmonic and Spurious Emission : -60dBc
RX to TX Transition Time : 8ms

Receiver

Frequency

: 851 ~ 866MHz

Sensitivity Static

: -114dBm for the MDC

: -94dBm for the RD_LAP

Adjacent and Alternate Channel Selectivity : 40dB/45dB for the Data

55dB/60dB for the Tone

CO-Channel Decode Ratio

: 8dB for the MDC

: 16dB for the RD_LAP

Spurious Response Attenuation : 60dBc
Image Frequency rejection : 50dBc

3. Circuit guide

A. RF circuit

CNI-803D circuit is composed of five parts such as power supply, antenna,

synthesis/modulation of frequency, transmission and reception.

power supply

Power supply is composed of voltage regulator and switching part. Voltage regulator
generates 3V of power supplied from VBB when the control of RF_EN switch is turned on.
When RF_EN is high, RF_VCC is regulated with 3V, and RF_VCC is supplied to PLL IC,
VCTCXO, OP-Amp(IC102), VCO, and Drive Amp(Q104).

When RX_EN is low, RX_VCC is turned on by Q202, and RX_VCC (3V) is supplied to

LNA, MIXER, IF AMP and IF IC.

When TX_EN is low, TX_VCC is turned on by Q201, and TX_VCC (3V) is supplied to

Buffer Amp(Q105) and OP-Amp(IC104).

The switch between TX mode and RX mode can be achieved by control of RX_EN(Q202)
and TX_EN(Q201).

2 Antenna

Antenna part is composed of antenna matching circuit, BPF, and Rx/Tx signal isolation
circuit.

CNI-803D adapts



/4 WHIP antenna to match to mid range frequency of communication.

TX/RX signal isolation circuit isolates signals of communication and is composed of
switching diode and inductor.

The signals received from antenna meet the send/receive path and then D1 is turned on
and the signals proceed only to receiving path. In receiving mode, signals from TX Power
Amp can not go through RX path because D101 is off. (refer to RF circuit diagram)

Frequency synthesizer and modulator

Frequency synthesizer consists of PLL part, VCO module and pre-modulation filter. The
PLL part is composed of phase detector, loop filter, and 12.6Mhz VCTCXO

VCO module generates 806~821Mhz frequencies in accordance with the voltage which is
from charge pump of PLL to loop filter. Programmable Divider in PLL makes the VCO
output frequency to any channel value according to the frequency data from  Logic CPU.
Phase detector gets low and high frequencies from comparison of phase.  Loop filter filters
the frequencies to get a value of voltage.  The voltage is input to VCO to achieve phase
lock process.

Modulation is completed when modem IC signal of Logic part is input to VCO and
authorized.

4 Receiver

Receiver filters and amplifies RF signal through SAW filter and LNA

RX part is double super heterodyne type, and consists of LNA, LPF, Mixer, SAW filter and
IF IC part. There happens RX signal from antenna and the signal is low-noise-
amplification (LNA) through SAW filter and LNA, and it comes to 2nd IF 455KHz via 2nd
X-TAL44.545MHz.

SAW filter rejects Image frequency(RX

2*IF) generated from 1’st Mixer while receiving.

For example, if the input channel is 858Mhz, the output frequency would be 45Mhz from
mixer while local frequency is 813Mhz. However, if SAW filter will not filter the image
frequency of 858

2*IF, S/N would be worse with 45Mhz(813-768=45) of noise. And SAW

filter should filter to prevent local frequency becoming spurious through LNA and reverse
path.
LNA amplifies and sends the faint signal from antenna to mixer, and mixer TR mixes and
generates 1st IF with frequency from antenna.

IF comes from mixer. And IF contains inter-modulation product component. MCF
removes that product component. So clean IF(45MHz) can be inserted to IF IC. 2nd local
frequency entered IF IC is mixed with the IF(45MHz) signal to be 2nd IF of 455KHz
simultaneously.

2nd IF signal of 455KHz passes LPF(Ceramic filer) to remove the noise, and the signal is
de-modulated with discriminator method. Here detected RF signal entered into receiver
and RSSI signal which indicates the strength, and they are passed to micro processor in
analogue value.

5 Transmitter

Transmitter consists of driver amp and power amplifier, and TX power control. It
generates carrier frequency while share RX with frequency synthesizer.

Local frequency is used to direct transmission frequency because there is difference
between transmission and reception. So it only amplifies and propagates through PA
(Power Amp.) which can get high level of gain easily with low power.

B. LOGIC Circuit

1 Summary

This unit consists of CPU part, Decoder part, modem part, and power supply part.

2 CPU

part(IC3)

The CPU adopted by this unit has 16/32-bit ARM7TDMI RISC processor (66MHz)
and works on 4.9152MHz. The main functions are as follows;

Execute MASC protocol

Control PLL circuit of R/F part and perform Power Saving function

Perform Data transaction function( receiving and transmitting) through Data
Pump(Modem)part

Checking and processing of RSSI Level come from R/F part

Perform Data transaction with DTE through DTE interface part

Memory part(IC1, IC3)

Memory part consists of FLASH Memory(2Mb, IC1) and SRAM(2Mb, IC3). Flash

Memory stores LLI information and program. And SRAM supplies memory stacks for
program.

4 Decoder

Part(IC6)

Decoder decodes control signal of CPU and generates SRAM memory choosing
signal.

Modem Data Pump(IC7)

Modem part is in charge of NCL protocol , and transmits two way Data between CPU
and RF part. The main functions are as followings ;

Packet Data Framing

FSK Data Modulation

FEC Encoding/Decoding

Interleaving/De-interleaving

4.Installation Guide

Modem Descriptions
1.

Physical Dimensions

Serial Interface between Application DTE

Power Supply and Current Usage

Design Consideration
1.

Product Applications

1.1

Use for Portable Terminal

1.2

Use for fixed mount

Installation
1.

Mounting

1.1

Fastening

1.2

Grounding

Warning Label

Antenna Spec.

1.physical
Dimensions

2. Serial Interface Between Application DTE

This unit can be easily integrated into anywhere of the wireless modem adopted

device.

1. RESET

: External Reset

11. SENSE4

: Status Input 4

2. TXD

: Transmit Data

12. DSR

: Data Set Ready

3. PWRON

: RPM Power On/Off

13. MAGWAIT

: Message Wait

4. RXD

: Receive Data

14. DCD

: Data Carrier Detect

5. SENSE1

: Status Input 1

15. INRANE

: In Range Indicator

6. RTS

: Request to Send

16. RI

: Ring Indicator

7. SENSE2

: Status Input 2

17. LOWBATT

: Low Battery

8. CTS

: Clear to Send

18. 5V PWR

: 5V Power Supply

9. SENSE3

: Status Input 3

19. GND

: Ground to Host

10. DTR

: Data Transmit Ready

20. 5V PWR

: 5V Power Supply

INTERFACE CIRCUIT OF CNI-803D

MSGWAIT

TxDA

VCC

HOST

CPU

PWRON

LOWBATT

HOST

VCC

SENSE1-4

SENSE

HOST

VCC

CPU

INRANGE

RTS

HOST

VCC

DSR

RXD

VCC

CPU

DTR

INDICATE

RxDA

VCC

CPU

CTS

VCC

RESET

DCD

TXD

3. Power Supply and Current Usage

3.1

Example of Power Supply from out-source : input Voltage 5V

10%,

more than 3A

3.1

3.2 Current Usage
TX :

2000mA

RX :

78A

Stand-By

: 12mA

Design Considerations

To integrate a wireless modem, there are several issues that need to be addressed and
considered. Internal connections and placement are critical to a successful
implementation. A successful design requires attention to several support
mechanisms as following:

DC Power

Serial interface and control

Mechanical mounting

Software

Antenna

RF control

Production Applications

The OEM wireless modem is well suited for mobile and fixed applications. The
wireless modem enables user to send/receive data anytime anywhere, and can
provide communications for a wide variety of products

1.1

Portable Terminal Use

Portable designs produce good environment for an integrated modem. The
portable terminal is typically battery powered, subject to temperature extremes,
and designed to be physically strong. When designing portable device, user
needs to pay attention to the following issue:

DC power noise levels on the host interface

Minimum operating voltage levels

Device internal ambient temperature

Antenna gain and proximity to user

Mechanical design for drop, vibration, dust, salt and liquid spill.

Note : Regarding this last point, CNI-803D modem is designed on the assumption that
the host device will control these conditions

1.2

Fixed Mount Usage

Fixed-mount usage eliminates most of the mechanical constraints of handheld designs.
The core requirement applies, but fixed usage does not present any special conditions
to address.

Installation

Installing CNI-803D modem is very simple as follows:

Place the modem to connector on product housing, and apply a little
force to push it down to be connected.
Caution : Care not to bend or damage the connector pins.

Use four #2-56 UNC 2A machine screws to tie up the modem as the
figure shown below.

Connect modem connection cable to a small hole provided at the rear of
the modem.

Connect the modem connection cable to Antenna

Mounting

Proper mounting of the modem requires a combination of securely fastening it
within the product housing as well as adequately grounding the modem case to
the housing.

1.1

Fastening

Mount the modem to the rigid OEM product housing by using three #2-56
UNC 2A machine screws as the figure shown below:

1.2

Grounding

For CNI-803D modem, the pin number 19 of connector on the modem is
ground pin. So if user properly places the modem, ground is automatically
done.

Warning Label

Following warning label shall be attached on the devices using CNI-803D modem.

While this device is in operation, a separation distance of at least 20 centimeters
(7.87 inches) is maintained between radiating antenna and the body of the user
or nearby persons in order to meet the FCC RF exposure guidelines.

Antenna Spec.

Product Name :

Whip Antenna of 800MHz Range

MODEL : HA-850W-SSMA

Application

Τηισ σπεχιφιχατιον δεσχριβεσ

/4 WHIP ANTENNA used for frequency range of 800MHz

for

τρανσµισσιον ∆ΑΤΑ οφ ωιρελεσσ.

Conditions of using Antenna

€

Ηανδηελδ

€

Φιξεδ

€

Μοβιλε

€

Ουτδοορ

€

νδοορ

Οτηερσ

Shape of Antenna

Ρεφερ το ατταχηεδ δραωινγ Νο.11Τ−17−003

Electrical features and Performance

Item

Features/Performance

Remark

Frequency range

806 ~ 870 MHz

Nominal impedance

Ω

V.S.W.R

Below 1 : 2.0

Radiation

Omni-direction

Polarization

Vertical

Gain

Unity

Structural Specification

Item

Specification/Features

Remark

Radiator

Ø1.5 Speedo wire

Sleeve

Shrinkable Tube

F-Type Ø1.5

Connector

SMA-Plug

Ni-plating

Total length

2mm

Other features and performance

6.1

Temperature

Antenna shall not be deformed or damaged and shall satisfy “Clause 4” in this specification after

Placing Antenna at –30 and 70 for 96 hours.

6.2

Humidity

After placing Antenna at surrounding temp. 40

ωιτη ρελατιϖε ηυµιδιτψ οφ 90 ∼ 95 φορ 96

ηουρσ, αντεννα σηαλλ νοτ βε δεφορµεδ ορ δαµαγεδ, ανδ σηαλλ σατισφψ

“

Χλαυσε 4

”

ιν τηισ

σπεχιφιχατιον

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